[Application Hosting and Deployment] Documentation for updating Kubernetes manifest

Description

The next step after https://vfs.atlassian.net/wiki/spaces/OT/pages/2350645620/Build+a+Helm+chart+for+EKS should be explaining how to add automation to keep the Kubernetes manifest up-to-date when a new version of the app's container is pushed to ECR. Example.

This used to be part of the onboarding checklist, but we took it out of there since this will happen after their app is onboarded.

Notes around work that is happening, if applicable (optional, please delete if unused)

[ ] Create document within this space https://vfs.atlassian.net/wiki/spaces/OT/pages/2348909545/Manage+applications+in+EKS
[ ] Add a link as "next steps" to the previous step

[x] Please attach your team label and any other appropriate label(s) (operations, devops, and needs-grooming will automatically be applied as part of the template)
[x] Please connect to an epic (this will typically be done by the Platform Operations PM or TL)